Regulation of Hydrogen Acceptance Capacity of Mgo to Enhance Ammonia Synthesis Rate of Cs-Ru/Mgo by Hydrogen Spillover

作     者：Huang, Jia Jiang, Xingmao You, Zhixiong 

作者机构：Key Laboratory for Green Chemical Process Ministry of Education Hubei Key Lab of Novel Reaction & Green Chemical Technology School of Chemical Engineering and Pharmacy Wuhan Institute of Technology Wuhan430205 China School of Resources and Environmental Sciences Wuhan University Wuhan430079 China 

出 版 物：《SSRN》 

年 卷 期：2022年

核心收录：

主　　题：Magnesia 

摘      要：Efficient ammonia synthesis is a significant but challenging target. One of questions to be faced in the Ru-based ammonia synthesis catalyst is the ill hydrogen poison effect of Ru. In this work, we developed a strategy to greatly alleviate the effect by regulating hydrogen acceptance capacity of support MgO, thereby promoting the ammonia synthesis rate. To this end, three kinds of MgO (MgO-c, MgO-p and MgO-s) with the varying content of surface active oxygen were chosen as the carrier of Ru catalysts for the synthesis of ammonia. The H2-TPR, in situ FTIR and EPR characterizations show that MgO-c supports have more active oxygen which can accept hydrogen atoms from the Ru surface as compared to the other two kinds of MgO. The kinetic analysis results show that the value of the hydrogen reaction order is 4Cs-Ru/MgO-c 2Cs-Ru/MgO-p Cs-Ru/MgO-s 0, indicating that no hydrogen poisoning occurs. Moreover, a positive and linear relationship was found between the ammonia synthesis rates over three Cs-Ru/MgO catalysts and their hydrogen reaction orders, confirming the crucial role of the alleviated hydrogen poison effect in the enhanced ammonia synthesis rate. Therefore, MgO containing abundant active oxygen can be expected to be a promising commercial catalyst carrier for Ru-based ammonia synthesis. © 2022, The Authors. All rights reserved.